May 17, 1912] 
“On the Reported Discovery of Radium in 
Arkansas,’’? A. H. Purdue, former state geologist 
of Arkansas. 
“‘Neon and Wireless Waves,’’ William L. Dud- 
ley, Vanderbilt University. 
“*Rock Striations and their Causes,’’ Chas. H. 
Gordon, University of Tennessee. 
‘¢Railroad and Road-building in Tennessee be- 
fore Civil War,’’ Gus Dyer, Vanderbilt University. 
‘<The Beginning of Music,’’? R. M. Ogden, Uni- 
versity of Tennessee. 
“*Food and Drug Inspection in Tennessee,’’” 
Lucius P. Brown, Tennessee Food and Drug In- 
spection. 
“Review of ‘History of Geological Work in 
Tennessee,’ ’’? L. C. Glenn, Vanderbilt University. 
‘*Some Remarkable Phenomena of the Tornado 
in Montgomery County, Tennessee, April 29, 
1909,’’? James A. Lyon, S. P. University. 
“Some Effects of Parasitic Fungi on Leaf Tis- 
sue,’’ Ernest S. Reynolds, University of Tennessee. 
‘¢Photomicrography in Colors by the Lumiére 
Process’’ (illustrated); ‘‘An Apparatus for 
Washing Fixed Microscopie Material’’ (illus- 
trated), Samuel M. Bain, University of Tennessee. 
‘‘T™he Selection of Food in Unicellular Ani- 
mals’’ (illustrated), Asa A. Schaeffer, University 
of Tennessee. 
“‘Blectrieal Conductivity in Dental Fillings,’’ 
John Daniels, Vanderbilt University. 
Wiupur A. NELSON, 
Secretary 
THE ACADEMY OF SCIENCE OF ST. LOUIS 
THE meeting of the academy was held at the 
academy building on Monday, April 1, 1912, at 
8 P.M., President Engler in the chair. 
Dr. G. O. James, of Washington University, 
addressed the academy on ‘‘The Application of 
the Relativity of Gravitation to the Motion of the 
Perihelion of Mercury.’’ 
J. L. Van Ornum, professor of civil engineering 
at Washington University, reviewed the methods 
practicably applicable to prevent dampness in 
tubble masonry foundation walls; that is, by 
drainage or by an impervious coating of their 
exterior, or by both. Impermeability may be 
attained by constructing an impervious diaphragm 
of a bituminous material; by an efficient surface 
coating, preferably on the outside; by carefully 
securing a maximum density by properly propor- 
tioning the components of the concrete; or by 
mixing with the concrete certain colloidal (or 
SCIENCE 
795 
other) substances to secure this result. The latter 
two methods have been experimentally investigated 
in successive years as thesis work by H. F. Mc- 
Farland, P. C. Grace, S. Johnson and W. K. Bege- 
man. Their results agree in general with those of 
others in concluding that, for any usual conditions, 
the patented mixtures sold for this purpose vary 
in effectiveness from very poor to very good; and 
that proper proportioning of the constituents of 
the concrete to attain a maximum density, such as 
is desirable to secure a maximum strength, will 
also effect practical impermeability; but they 
differ from the conclusions of some others in the 
fact that they found no advantage to result from 
the incorporation of such a material as hydrated 
lime in the richer mixtures. 
The apparatus designed by the students for 
these experiments, which gave pressure up to forty 
pounds per square inch, was planned to eliminate 
certain features of the experimental devices of 
others which seemed objectionable to them; par- 
ticularly in eliminating tensile stresses from the 
specimens tested, with the resulting tendency to 
form cracks. 
Professor Nipher gave a preliminary discussion 
of a phenomenon observed by Planté. It is the 
buckling of a fine wire through which an electric 
discharge is passed. Professor Nipher finds that 
a long and very fine fuse-wire of lead, lying on a 
strip of glass, usually breaks at the positive end, 
at a point where it is made fast by sealing wax. 
The wire at the same time is urged towards the 
negative terminal, as positive ions are in a gap of 
air. The metal wire behaves like the positive 
column in discharge through gases. The negative 
end of the wire appears to be urged in the opposite 
direction, as is also the case at the negative ter- 
minal in discharge through gases. It sometimes 
happens that the wire breaks down at the negative 
end. Nearly all of the wire, however, appears to 
have the property of the positive column. It is 
urged longitudinally in a direction opposite to that 
in which the negative corpuscles are being con- 
ducted. Fine copper wire is now being used, and 
the ends of the wire are left free to move, while 
the wire is sealed to the glass strip at various 
intermediate points. The conditions which deter- 
mine the limiting point between portions of the 
wire which are being urged in opposite directions 
have not yet been fully ascertained. The positive 
ions which constitute the copper wire are not 
quite as free to ‘‘wander’’ as they are in the case 
of solutions, or in discharge through gases. 
